In {{y_est}}, up to {{phi}} per cent of the ethane in U.S. gas, a raw material for plastic, was burned as fuel instead, because too few plastics plants and export ships could take it
Why it matters: ethane left in the gas does not become plastic; it goes to gas users with the rest of the gas and is burned in their furnaces, stoves and power plants, and it makes the gas hotter. The U.S. Energy Information Administration (EIA) found that in July {{y_heat}} the gas delivered in West Virginia carried {{wv}} per cent more heat than the national average, and in North Dakota {{nd}} per cent more, which it said may indicate ethane left in; and that "{{q_stoves}}" (Btu, British thermal units, measure heat). The choice is made at gas processing plants, which can take the ethane out of the gas and sell it as a liquid, mostly to be made into ethylene for plastics, or leave it in. EIA calls leaving it in ethane rejection. In May {{y_est}} EIA reported estimates of {{lo}} to {{hi}} barrels a day, about {{plo}} to {{phi}} per cent of the ethane in the gas the plants processed. Plants have taken more of it out since, as plastics plants and export ships took more, but EIA wrote in {{y_rec1}} that ethane can still be left in when its price comes close to that of gas.
Archived page. {{archived}}
{{takeaways}}Ethane against the other liquids
Gas plants produce five liquids: ethane, propane, two butanes and natural gasoline. More gas processed means more of all of them, so a rising volume of ethane says little on its own. Ethane's share of the five says more, because ethane is the one EIA singles out: "{{q_unlike}}". When plants leave ethane in, its share falls. EIA used the same measure in {{y_28052}}, reporting the share's fall from {{s2010r}} per cent in 2010 to {{s2015r}} per cent in 2015.
The chart shows ethane's share month by month; it swings by a few points within each year. Below it, ethane and propane production, each on its own scale.
{{hero}}EIA's monthly field production of natural gas plant liquids, {{x0}} to {{x1}}, as fetched on {{fetched}}; the latest months are preliminary and are revised. The share is ethane over EIA's total for the five liquids.
What EIA said about the price
In EIA's account, ethane sold for about the price of natural gas, measured by the heat each carries, from late 2012 to mid-2017, and at a premium since. This page found no ethane price series that is free to republish, so it computes no price signal of its own and gives EIA's words, at the dates EIA wrote them.
| EIA, when | What it wrote |
|---|
Prices are for ethane at Mont Belvieu, Texas, in EIA's words "{{q_hub}}". MMBtu is a million British thermal units, a measure of heat; EIA gives ethane's approximate heat content as {{btu}} MMBtu a barrel, so a price per gallon and a price per MMBtu can be compared.
The price is not the whole of it. In {{y_25632}}, EIA described what had changed: "{{q_wave}}". It dated the first ship exports of ethane, from a terminal at Marcus Hook, Pennsylvania, to {{first_ship}}, and wrote in {{y_39712}} that "{{q_crackers}}", and that ethane is recovered "{{q_costs}}". Of the record year {{y_rec}}, it wrote: "{{q_2024_causes}}".
Method
Volumes. EIA's monthly field production of natural gas plant liquids by product, United States, thousand barrels a day: ethane, propane, normal butane, isobutane and natural gasoline, and their total, which the build checks equals the sum of the five each month. A year's share is the mean of its months' shares; the share over the latest twelve months, {{ttm_from}} to {{ttm_to}}, is their ethane over their total. Growth since {{g_base}} compares the latest twelve months with {{g_base}}'s average. EIA has also compared ethane with the gas produced: in {{y_ngwu}} it wrote that "{{q_test}}". This page uses the share because it is national and monthly.
The {{y_est}} estimate. "{{q_estimates_full}}" (thousand barrels a day), EIA wrote on {{d_16191}}, without saying whose estimates they were. Against the {{rec}} thousand barrels a day plants recovered on average in {{y_est}}, that range is {{plo1}} to {{phi1}} per cent of the ethane recovered and left in together.
Checked against EIA. The build reproduces figures EIA printed from the same series, among them ethane's share, {{s2010r}} per cent in 2010 and {{s2015r}} per cent in 2015, and {{y2018}} million barrels a day in 2018; the code lists all of them. Statements of EIA's that the series does not reproduce are left off the page.
Limits
This is a record of what EIA published, not a model. Without a price series it cannot say month by month when recovering ethane paid; it can only show the volumes and repeat what EIA wrote. The share moves with the gas itself, wetter or drier from one basin to the next, as well as with how much ethane plants leave in, so it shows the direction of rejection, not its amount, and it cannot show how much ethane is still left in the gas today. EIA wrote in {{y_rec1}} that "{{q_closer}}". The totals are national: EIA found rejection "{{q_places}}", and a national share blurs where it happened.
The code
Python: the fetch script, recording where and when each EIA file came from; the readers, which read every figure and quotation out of those files; the payload builder with its checks against EIA's printed figures; the page generator; and the tests. The archive carries the payload, not EIA's files. {{zip_kb}} KB.